fix: secondary process crash

[pengjianzhang]

the secondary process cannot memset spp_dev to zero.

[kyyalama2]

Can you please elaborate, what the issue seen was (if its failing a particular use-case, seeing errors etc) and how the update fixes the issue. Thanks

[pengjianzhang]

I start a primary process and then a secondary process; the primary process crashes. The location of the crash is in the function spp_tx_process_status(), and the statement "uint32_t status = tx_chan->tx_info.tx_status->status" accesses address zero.

The reason is that the secondary process cleared this memory by function eth_spp_init().
The secondary process can only attach these data structures and cannot modify them. I put 'memset' after checking the process's type.

[pengjianzhang]

rx_chan was cleared